X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/706b88074de0c288b81edac13094dd052b6cc078..43f4e852a1b2ac37c3db6a2b87315192ac549191:/src/png/pngset.c?ds=inline

diff --git a/src/png/pngset.c b/src/png/pngset.c
index b9677a12dd..92db3890a8 100644
--- a/src/png/pngset.c
+++ b/src/png/pngset.c
@@ -1,26 +1,32 @@
 
 /* pngset.c - storage of image information into info struct
  *
- * libpng 1.2.7 - September 12, 2004
- * For conditions of distribution and use, see copyright notice in png.h
- * Copyright (c) 1998-2004 Glenn Randers-Pehrson
+ * Last changed in libpng 1.5.7 [December 15, 2011]
+ * Copyright (c) 1998-2011 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
  *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
  * The functions here are used during reads to store data from the file
  * into the info struct, and during writes to store application data
  * into the info struct for writing into the file.  This abstracts the
  * info struct and allows us to change the structure in the future.
  */
 
-#define PNG_INTERNAL
-#include "png.h"
+#include "pngpriv.h"
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
 
-#if defined(PNG_bKGD_SUPPORTED)
+#ifdef PNG_bKGD_SUPPORTED
 void PNGAPI
-png_set_bKGD(png_structp png_ptr, png_infop info_ptr, png_color_16p background)
+png_set_bKGD(png_structp png_ptr, png_infop info_ptr,
+    png_const_color_16p background)
 {
-   png_debug1(1, "in %s storage function\n", "bKGD");
+   png_debug1(1, "in %s storage function", "bKGD");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
@@ -29,332 +35,242 @@ png_set_bKGD(png_structp png_ptr, png_infop info_ptr, png_color_16p background)
 }
 #endif
 
-#if defined(PNG_cHRM_SUPPORTED)
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-void PNGAPI
-png_set_cHRM(png_structp png_ptr, png_infop info_ptr,
-   double white_x, double white_y, double red_x, double red_y,
-   double green_x, double green_y, double blue_x, double blue_y)
+#ifdef PNG_cHRM_SUPPORTED
+void PNGFAPI
+png_set_cHRM_fixed(png_structp png_ptr, png_infop info_ptr,
+    png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
+    png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
+    png_fixed_point blue_x, png_fixed_point blue_y)
 {
-   png_debug1(1, "in %s storage function\n", "cHRM");
+   png_debug1(1, "in %s storage function", "cHRM fixed");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   if (white_x < 0.0 || white_y < 0.0 ||
-         red_x < 0.0 ||   red_y < 0.0 ||
-       green_x < 0.0 || green_y < 0.0 ||
-        blue_x < 0.0 ||  blue_y < 0.0)
-   {
-      png_warning(png_ptr,
-        "Ignoring attempt to set negative chromaticity value");
-      return;
-   }
-   if (white_x > 21474.83 || white_y > 21474.83 ||
-         red_x > 21474.83 ||   red_y > 21474.83 ||
-       green_x > 21474.83 || green_y > 21474.83 ||
-        blue_x > 21474.83 ||  blue_y > 21474.83)
+#  ifdef PNG_CHECK_cHRM_SUPPORTED
+   if (png_check_cHRM_fixed(png_ptr,
+       white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y))
+#  endif
    {
-      png_warning(png_ptr,
-        "Ignoring attempt to set chromaticity value exceeding 21474.83");
-      return;
+      info_ptr->x_white = white_x;
+      info_ptr->y_white = white_y;
+      info_ptr->x_red   = red_x;
+      info_ptr->y_red   = red_y;
+      info_ptr->x_green = green_x;
+      info_ptr->y_green = green_y;
+      info_ptr->x_blue  = blue_x;
+      info_ptr->y_blue  = blue_y;
+      info_ptr->valid |= PNG_INFO_cHRM;
    }
-
-   info_ptr->x_white = (float)white_x;
-   info_ptr->y_white = (float)white_y;
-   info_ptr->x_red   = (float)red_x;
-   info_ptr->y_red   = (float)red_y;
-   info_ptr->x_green = (float)green_x;
-   info_ptr->y_green = (float)green_y;
-   info_ptr->x_blue  = (float)blue_x;
-   info_ptr->y_blue  = (float)blue_y;
-#ifdef PNG_FIXED_POINT_SUPPORTED
-   info_ptr->int_x_white = (png_fixed_point)(white_x*100000.+0.5);
-   info_ptr->int_y_white = (png_fixed_point)(white_y*100000.+0.5);
-   info_ptr->int_x_red   = (png_fixed_point)(  red_x*100000.+0.5);
-   info_ptr->int_y_red   = (png_fixed_point)(  red_y*100000.+0.5);
-   info_ptr->int_x_green = (png_fixed_point)(green_x*100000.+0.5);
-   info_ptr->int_y_green = (png_fixed_point)(green_y*100000.+0.5);
-   info_ptr->int_x_blue  = (png_fixed_point)( blue_x*100000.+0.5);
-   info_ptr->int_y_blue  = (png_fixed_point)( blue_y*100000.+0.5);
-#endif
-   info_ptr->valid |= PNG_INFO_cHRM;
 }
-#endif
-#ifdef PNG_FIXED_POINT_SUPPORTED
-void PNGAPI
-png_set_cHRM_fixed(png_structp png_ptr, png_infop info_ptr,
-   png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x,
-   png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y,
-   png_fixed_point blue_x, png_fixed_point blue_y)
+
+void PNGFAPI
+png_set_cHRM_XYZ_fixed(png_structp png_ptr, png_infop info_ptr,
+    png_fixed_point int_red_X, png_fixed_point int_red_Y,
+    png_fixed_point int_red_Z, png_fixed_point int_green_X,
+    png_fixed_point int_green_Y, png_fixed_point int_green_Z,
+    png_fixed_point int_blue_X, png_fixed_point int_blue_Y,
+    png_fixed_point int_blue_Z)
 {
-   png_debug1(1, "in %s storage function\n", "cHRM");
+   png_XYZ XYZ;
+   png_xy xy;
+
+   png_debug1(1, "in %s storage function", "cHRM XYZ fixed");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   if (white_x < 0 || white_y < 0 ||
-         red_x < 0 ||   red_y < 0 ||
-       green_x < 0 || green_y < 0 ||
-        blue_x < 0 ||  blue_y < 0)
-   {
-      png_warning(png_ptr,
-        "Ignoring attempt to set negative chromaticity value");
-      return;
-   }
-   if (white_x > (double) PNG_UINT_31_MAX ||
-       white_y > (double) PNG_UINT_31_MAX ||
-         red_x > (double) PNG_UINT_31_MAX ||
-         red_y > (double) PNG_UINT_31_MAX ||
-       green_x > (double) PNG_UINT_31_MAX ||
-       green_y > (double) PNG_UINT_31_MAX ||
-        blue_x > (double) PNG_UINT_31_MAX ||
-        blue_y > (double) PNG_UINT_31_MAX)
-   {
-      png_warning(png_ptr,
-        "Ignoring attempt to set chromaticity value exceeding 21474.83");
-      return;
-   }
-   info_ptr->int_x_white = white_x;
-   info_ptr->int_y_white = white_y;
-   info_ptr->int_x_red   = red_x;
-   info_ptr->int_y_red   = red_y;
-   info_ptr->int_x_green = green_x;
-   info_ptr->int_y_green = green_y;
-   info_ptr->int_x_blue  = blue_x;
-   info_ptr->int_y_blue  = blue_y;
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-   info_ptr->x_white = (float)(white_x/100000.);
-   info_ptr->y_white = (float)(white_y/100000.);
-   info_ptr->x_red   = (float)(  red_x/100000.);
-   info_ptr->y_red   = (float)(  red_y/100000.);
-   info_ptr->x_green = (float)(green_x/100000.);
-   info_ptr->y_green = (float)(green_y/100000.);
-   info_ptr->x_blue  = (float)( blue_x/100000.);
-   info_ptr->y_blue  = (float)( blue_y/100000.);
-#endif
-   info_ptr->valid |= PNG_INFO_cHRM;
+   XYZ.redX = int_red_X;
+   XYZ.redY = int_red_Y;
+   XYZ.redZ = int_red_Z;
+   XYZ.greenX = int_green_X;
+   XYZ.greenY = int_green_Y;
+   XYZ.greenZ = int_green_Z;
+   XYZ.blueX = int_blue_X;
+   XYZ.blueY = int_blue_Y;
+   XYZ.blueZ = int_blue_Z;
+
+   if (png_xy_from_XYZ(&xy, XYZ))
+      png_error(png_ptr, "XYZ values out of representable range");
+
+   png_set_cHRM_fixed(png_ptr, info_ptr, xy.whitex, xy.whitey, xy.redx, xy.redy,
+      xy.greenx, xy.greeny, xy.bluex, xy.bluey);
 }
-#endif
-#endif
 
-#if defined(PNG_gAMA_SUPPORTED)
-#ifdef PNG_FLOATING_POINT_SUPPORTED
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
 void PNGAPI
-png_set_gAMA(png_structp png_ptr, png_infop info_ptr, double file_gamma)
+png_set_cHRM(png_structp png_ptr, png_infop info_ptr,
+    double white_x, double white_y, double red_x, double red_y,
+    double green_x, double green_y, double blue_x, double blue_y)
 {
-   double gamma;
-   png_debug1(1, "in %s storage function\n", "gAMA");
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
-
-   /* Check for overflow */
-   if (file_gamma > 21474.83)
-   {
-      png_warning(png_ptr, "Limiting gamma to 21474.83");
-      gamma=21474.83;
-   }
-   else
-      gamma=file_gamma;
-   info_ptr->gamma = (float)gamma;
-#ifdef PNG_FIXED_POINT_SUPPORTED
-   info_ptr->int_gamma = (int)(gamma*100000.+.5);
-#endif
-   info_ptr->valid |= PNG_INFO_gAMA;
-   if(gamma == 0.0)
-      png_warning(png_ptr, "Setting gamma=0");
+   png_set_cHRM_fixed(png_ptr, info_ptr,
+      png_fixed(png_ptr, white_x, "cHRM White X"),
+      png_fixed(png_ptr, white_y, "cHRM White Y"),
+      png_fixed(png_ptr, red_x, "cHRM Red X"),
+      png_fixed(png_ptr, red_y, "cHRM Red Y"),
+      png_fixed(png_ptr, green_x, "cHRM Green X"),
+      png_fixed(png_ptr, green_y, "cHRM Green Y"),
+      png_fixed(png_ptr, blue_x, "cHRM Blue X"),
+      png_fixed(png_ptr, blue_y, "cHRM Blue Y"));
 }
-#endif
+
 void PNGAPI
+png_set_cHRM_XYZ(png_structp png_ptr, png_infop info_ptr, double red_X,
+    double red_Y, double red_Z, double green_X, double green_Y, double green_Z,
+    double blue_X, double blue_Y, double blue_Z)
+{
+   png_set_cHRM_XYZ_fixed(png_ptr, info_ptr,
+      png_fixed(png_ptr, red_X, "cHRM Red X"),
+      png_fixed(png_ptr, red_Y, "cHRM Red Y"),
+      png_fixed(png_ptr, red_Z, "cHRM Red Z"),
+      png_fixed(png_ptr, green_X, "cHRM Red X"),
+      png_fixed(png_ptr, green_Y, "cHRM Red Y"),
+      png_fixed(png_ptr, green_Z, "cHRM Red Z"),
+      png_fixed(png_ptr, blue_X, "cHRM Red X"),
+      png_fixed(png_ptr, blue_Y, "cHRM Red Y"),
+      png_fixed(png_ptr, blue_Z, "cHRM Red Z"));
+}
+#  endif /* PNG_FLOATING_POINT_SUPPORTED */
+
+#endif /* PNG_cHRM_SUPPORTED */
+
+#ifdef PNG_gAMA_SUPPORTED
+void PNGFAPI
 png_set_gAMA_fixed(png_structp png_ptr, png_infop info_ptr, png_fixed_point
-   int_gamma)
+    file_gamma)
 {
-   png_fixed_point gamma;
+   png_debug1(1, "in %s storage function", "gAMA");
 
-   png_debug1(1, "in %s storage function\n", "gAMA");
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   if (int_gamma > (png_fixed_point) PNG_UINT_31_MAX)
-   {
-     png_warning(png_ptr, "Limiting gamma to 21474.83");
-     gamma=PNG_UINT_31_MAX;
-   }
+   /* Changed in libpng-1.5.4 to limit the values to ensure overflow can't
+    * occur.  Since the fixed point representation is assymetrical it is
+    * possible for 1/gamma to overflow the limit of 21474 and this means the
+    * gamma value must be at least 5/100000 and hence at most 20000.0.  For
+    * safety the limits here are a little narrower.  The values are 0.00016 to
+    * 6250.0, which are truly ridiculous gammma values (and will produce
+    * displays that are all black or all white.)
+    */
+   if (file_gamma < 16 || file_gamma > 625000000)
+      png_warning(png_ptr, "Out of range gamma value ignored");
+
    else
    {
-     if (int_gamma < 0)
-     {
-       png_warning(png_ptr, "Setting negative gamma to zero");
-       gamma=0;
-     }
-     else
-       gamma=int_gamma;
+      info_ptr->gamma = file_gamma;
+      info_ptr->valid |= PNG_INFO_gAMA;
    }
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-   info_ptr->gamma = (float)(gamma/100000.);
-#endif
-#ifdef PNG_FIXED_POINT_SUPPORTED
-   info_ptr->int_gamma = gamma;
-#endif
-   info_ptr->valid |= PNG_INFO_gAMA;
-   if(gamma == 0)
-      png_warning(png_ptr, "Setting gamma=0");
 }
+
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
+void PNGAPI
+png_set_gAMA(png_structp png_ptr, png_infop info_ptr, double file_gamma)
+{
+   png_set_gAMA_fixed(png_ptr, info_ptr, png_fixed(png_ptr, file_gamma,
+       "png_set_gAMA"));
+}
+#  endif
 #endif
 
-#if defined(PNG_hIST_SUPPORTED)
+#ifdef PNG_hIST_SUPPORTED
 void PNGAPI
-png_set_hIST(png_structp png_ptr, png_infop info_ptr, png_uint_16p hist)
+png_set_hIST(png_structp png_ptr, png_infop info_ptr, png_const_uint_16p hist)
 {
    int i;
 
-   png_debug1(1, "in %s storage function\n", "hIST");
+   png_debug1(1, "in %s storage function", "hIST");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
-   if (info_ptr->num_palette == 0)
+
+   if (info_ptr->num_palette == 0 || info_ptr->num_palette
+       > PNG_MAX_PALETTE_LENGTH)
    {
-       png_warning(png_ptr,
-          "Palette size 0, hIST allocation skipped.");
-       return;
+      png_warning(png_ptr,
+          "Invalid palette size, hIST allocation skipped");
+
+      return;
    }
 
-#ifdef PNG_FREE_ME_SUPPORTED
    png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0);
-#endif
-   /* Changed from info->num_palette to 256 in version 1.2.1 */
+
+   /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in
+    * version 1.2.1
+    */
    png_ptr->hist = (png_uint_16p)png_malloc_warn(png_ptr,
-      (png_uint_32)(256 * png_sizeof (png_uint_16)));
+       PNG_MAX_PALETTE_LENGTH * png_sizeof(png_uint_16));
+
    if (png_ptr->hist == NULL)
-     {
-       png_warning(png_ptr, "Insufficient memory for hIST chunk data.");
-       return;
-     }
+   {
+      png_warning(png_ptr, "Insufficient memory for hIST chunk data");
+      return;
+   }
 
    for (i = 0; i < info_ptr->num_palette; i++)
-       png_ptr->hist[i] = hist[i];
+      png_ptr->hist[i] = hist[i];
+
    info_ptr->hist = png_ptr->hist;
    info_ptr->valid |= PNG_INFO_hIST;
-
-#ifdef PNG_FREE_ME_SUPPORTED
    info_ptr->free_me |= PNG_FREE_HIST;
-#else
-   png_ptr->flags |= PNG_FLAG_FREE_HIST;
-#endif
 }
 #endif
 
 void PNGAPI
 png_set_IHDR(png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 width, png_uint_32 height, int bit_depth,
-   int color_type, int interlace_type, int compression_type,
-   int filter_type)
+    png_uint_32 width, png_uint_32 height, int bit_depth,
+    int color_type, int interlace_type, int compression_type,
+    int filter_type)
 {
-   png_debug1(1, "in %s storage function\n", "IHDR");
+   png_debug1(1, "in %s storage function", "IHDR");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   /* check for width and height valid values */
-   if (width == 0 || height == 0)
-      png_error(png_ptr, "Image width or height is zero in IHDR");
-#ifdef PNG_SET_USER_LIMITS_SUPPORTED
-   if (width > png_ptr->user_width_max || height > png_ptr->user_height_max)
-      png_error(png_ptr, "image size exceeds user limits in IHDR");
-#else
-   if (width > PNG_USER_WIDTH_MAX || height > PNG_USER_HEIGHT_MAX)
-      png_error(png_ptr, "image size exceeds user limits in IHDR");
-#endif
-   if (width > PNG_UINT_31_MAX || height > PNG_UINT_31_MAX)
-      png_error(png_ptr, "Invalid image size in IHDR");
-   if ( width > (PNG_UINT_32_MAX
-                 >> 3)      /* 8-byte RGBA pixels */
-                 - 64       /* bigrowbuf hack */
-                 - 1        /* filter byte */
-                 - 7*8      /* rounding of width to multiple of 8 pixels */
-                 - 8)       /* extra max_pixel_depth pad */
-      png_warning(png_ptr, "Width is too large for libpng to process pixels");
-
-   /* check other values */
-   if (bit_depth != 1 && bit_depth != 2 && bit_depth != 4 &&
-      bit_depth != 8 && bit_depth != 16)
-      png_error(png_ptr, "Invalid bit depth in IHDR");
-
-   if (color_type < 0 || color_type == 1 ||
-      color_type == 5 || color_type > 6)
-      png_error(png_ptr, "Invalid color type in IHDR");
-
-   if (((color_type == PNG_COLOR_TYPE_PALETTE) && bit_depth > 8) ||
-       ((color_type == PNG_COLOR_TYPE_RGB ||
-         color_type == PNG_COLOR_TYPE_GRAY_ALPHA ||
-         color_type == PNG_COLOR_TYPE_RGB_ALPHA) && bit_depth < 8))
-      png_error(png_ptr, "Invalid color type/bit depth combination in IHDR");
-
-   if (interlace_type >= PNG_INTERLACE_LAST)
-      png_error(png_ptr, "Unknown interlace method in IHDR");
-
-   if (compression_type != PNG_COMPRESSION_TYPE_BASE)
-      png_error(png_ptr, "Unknown compression method in IHDR");
-
-#if defined(PNG_MNG_FEATURES_SUPPORTED)
-   /* Accept filter_method 64 (intrapixel differencing) only if
-    * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
-    * 2. Libpng did not read a PNG signature (this filter_method is only
-    *    used in PNG datastreams that are embedded in MNG datastreams) and
-    * 3. The application called png_permit_mng_features with a mask that
-    *    included PNG_FLAG_MNG_FILTER_64 and
-    * 4. The filter_method is 64 and
-    * 5. The color_type is RGB or RGBA
-    */
-   if((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)&&png_ptr->mng_features_permitted)
-      png_warning(png_ptr,"MNG features are not allowed in a PNG datastream\n");
-   if(filter_type != PNG_FILTER_TYPE_BASE)
-   {
-     if(!((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) &&
-        (filter_type == PNG_INTRAPIXEL_DIFFERENCING) &&
-        ((png_ptr->mode&PNG_HAVE_PNG_SIGNATURE) == 0) &&
-        (color_type == PNG_COLOR_TYPE_RGB || 
-         color_type == PNG_COLOR_TYPE_RGB_ALPHA)))
-        png_error(png_ptr, "Unknown filter method in IHDR");
-     if(png_ptr->mode&PNG_HAVE_PNG_SIGNATURE)
-        png_warning(png_ptr, "Invalid filter method in IHDR");
-   }
-#else
-   if(filter_type != PNG_FILTER_TYPE_BASE)
-      png_error(png_ptr, "Unknown filter method in IHDR");
-#endif
-
    info_ptr->width = width;
    info_ptr->height = height;
    info_ptr->bit_depth = (png_byte)bit_depth;
-   info_ptr->color_type =(png_byte) color_type;
+   info_ptr->color_type = (png_byte)color_type;
    info_ptr->compression_type = (png_byte)compression_type;
    info_ptr->filter_type = (png_byte)filter_type;
    info_ptr->interlace_type = (png_byte)interlace_type;
+
+   png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height,
+       info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type,
+       info_ptr->compression_type, info_ptr->filter_type);
+
    if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
       info_ptr->channels = 1;
+
    else if (info_ptr->color_type & PNG_COLOR_MASK_COLOR)
       info_ptr->channels = 3;
+
    else
       info_ptr->channels = 1;
+
    if (info_ptr->color_type & PNG_COLOR_MASK_ALPHA)
       info_ptr->channels++;
+
    info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth);
 
-   /* check for potential overflow */
-   if ( width > (PNG_UINT_32_MAX
-                 >> 3)      /* 8-byte RGBA pixels */
-                 - 64       /* bigrowbuf hack */
-                 - 1        /* filter byte */
-                 - 7*8      /* rounding of width to multiple of 8 pixels */
-                 - 8)       /* extra max_pixel_depth pad */
-      info_ptr->rowbytes = (png_size_t)0;
+   /* Check for potential overflow */
+   if (width >
+       (PNG_UINT_32_MAX >> 3)      /* 8-byte RRGGBBAA pixels */
+       - 48       /* bigrowbuf hack */
+       - 1        /* filter byte */
+       - 7*8      /* rounding of width to multiple of 8 pixels */
+       - 8)       /* extra max_pixel_depth pad */
+      info_ptr->rowbytes = 0;
    else
-      info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth,width);
+      info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width);
 }
 
-#if defined(PNG_oFFs_SUPPORTED)
+#ifdef PNG_oFFs_SUPPORTED
 void PNGAPI
 png_set_oFFs(png_structp png_ptr, png_infop info_ptr,
-   png_int_32 offset_x, png_int_32 offset_y, int unit_type)
+    png_int_32 offset_x, png_int_32 offset_y, int unit_type)
 {
-   png_debug1(1, "in %s storage function\n", "oFFs");
+   png_debug1(1, "in %s storage function", "oFFs");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
@@ -365,139 +281,227 @@ png_set_oFFs(png_structp png_ptr, png_infop info_ptr,
 }
 #endif
 
-#if defined(PNG_pCAL_SUPPORTED)
+#ifdef PNG_pCAL_SUPPORTED
 void PNGAPI
 png_set_pCAL(png_structp png_ptr, png_infop info_ptr,
-   png_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams,
-   png_charp units, png_charpp params)
+    png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type,
+    int nparams, png_const_charp units, png_charpp params)
 {
-   png_uint_32 length;
+   png_size_t length;
    int i;
 
-   png_debug1(1, "in %s storage function\n", "pCAL");
+   png_debug1(1, "in %s storage function", "pCAL");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
    length = png_strlen(purpose) + 1;
-   png_debug1(3, "allocating purpose for info (%lu bytes)\n", length);
+   png_debug1(3, "allocating purpose for info (%lu bytes)",
+       (unsigned long)length);
+
+   /* TODO: validate format of calibration name and unit name */
+
+   /* Check that the type matches the specification. */
+   if (type < 0 || type > 3)
+      png_error(png_ptr, "Invalid pCAL equation type");
+
+   /* Validate params[nparams] */
+   for (i=0; i<nparams; ++i)
+      if (!png_check_fp_string(params[i], png_strlen(params[i])))
+         png_error(png_ptr, "Invalid format for pCAL parameter");
+
    info_ptr->pcal_purpose = (png_charp)png_malloc_warn(png_ptr, length);
+
    if (info_ptr->pcal_purpose == NULL)
-     {
-       png_warning(png_ptr, "Insufficient memory for pCAL purpose.");
-       return;
-     }
-   png_memcpy(info_ptr->pcal_purpose, purpose, (png_size_t)length);
+   {
+      png_warning(png_ptr, "Insufficient memory for pCAL purpose");
+      return;
+   }
+
+   png_memcpy(info_ptr->pcal_purpose, purpose, length);
 
-   png_debug(3, "storing X0, X1, type, and nparams in info\n");
+   png_debug(3, "storing X0, X1, type, and nparams in info");
    info_ptr->pcal_X0 = X0;
    info_ptr->pcal_X1 = X1;
    info_ptr->pcal_type = (png_byte)type;
    info_ptr->pcal_nparams = (png_byte)nparams;
 
    length = png_strlen(units) + 1;
-   png_debug1(3, "allocating units for info (%lu bytes)\n", length);
+   png_debug1(3, "allocating units for info (%lu bytes)",
+     (unsigned long)length);
+
    info_ptr->pcal_units = (png_charp)png_malloc_warn(png_ptr, length);
+
    if (info_ptr->pcal_units == NULL)
-     {
-       png_warning(png_ptr, "Insufficient memory for pCAL units.");
-       return;
-     }
-   png_memcpy(info_ptr->pcal_units, units, (png_size_t)length);
+   {
+      png_warning(png_ptr, "Insufficient memory for pCAL units");
+      return;
+   }
+
+   png_memcpy(info_ptr->pcal_units, units, length);
 
    info_ptr->pcal_params = (png_charpp)png_malloc_warn(png_ptr,
-      (png_uint_32)((nparams + 1) * png_sizeof(png_charp)));
+       (png_size_t)((nparams + 1) * png_sizeof(png_charp)));
+
    if (info_ptr->pcal_params == NULL)
-     {
-       png_warning(png_ptr, "Insufficient memory for pCAL params.");
-       return;
-     }
+   {
+      png_warning(png_ptr, "Insufficient memory for pCAL params");
+      return;
+   }
 
-   info_ptr->pcal_params[nparams] = NULL;
+   png_memset(info_ptr->pcal_params, 0, (nparams + 1) * png_sizeof(png_charp));
 
    for (i = 0; i < nparams; i++)
    {
       length = png_strlen(params[i]) + 1;
-      png_debug2(3, "allocating parameter %d for info (%lu bytes)\n", i, length);
+      png_debug2(3, "allocating parameter %d for info (%lu bytes)", i,
+          (unsigned long)length);
+
       info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length);
+
       if (info_ptr->pcal_params[i] == NULL)
-        {
-          png_warning(png_ptr, "Insufficient memory for pCAL parameter.");
-          return;
-        }
-      png_memcpy(info_ptr->pcal_params[i], params[i], (png_size_t)length);
+      {
+         png_warning(png_ptr, "Insufficient memory for pCAL parameter");
+         return;
+      }
+
+      png_memcpy(info_ptr->pcal_params[i], params[i], length);
    }
 
    info_ptr->valid |= PNG_INFO_pCAL;
-#ifdef PNG_FREE_ME_SUPPORTED
    info_ptr->free_me |= PNG_FREE_PCAL;
-#endif
 }
 #endif
 
-#if defined(PNG_READ_sCAL_SUPPORTED) || defined(PNG_WRITE_sCAL_SUPPORTED)
-#ifdef PNG_FLOATING_POINT_SUPPORTED
+#ifdef PNG_sCAL_SUPPORTED
 void PNGAPI
-png_set_sCAL(png_structp png_ptr, png_infop info_ptr,
-             int unit, double width, double height)
+png_set_sCAL_s(png_structp png_ptr, png_infop info_ptr,
+    int unit, png_const_charp swidth, png_const_charp sheight)
 {
-   png_debug1(1, "in %s storage function\n", "sCAL");
+   png_size_t lengthw = 0, lengthh = 0;
+
+   png_debug1(1, "in %s storage function", "sCAL");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   info_ptr->scal_unit = (png_byte)unit;
-   info_ptr->scal_pixel_width = width;
-   info_ptr->scal_pixel_height = height;
+   /* Double check the unit (should never get here with an invalid
+    * unit unless this is an API call.)
+    */
+   if (unit != 1 && unit != 2)
+      png_error(png_ptr, "Invalid sCAL unit");
 
-   info_ptr->valid |= PNG_INFO_sCAL;
-}
-#else
-#ifdef PNG_FIXED_POINT_SUPPORTED
-void PNGAPI
-png_set_sCAL_s(png_structp png_ptr, png_infop info_ptr,
-             int unit, png_charp swidth, png_charp sheight)
-{
-   png_uint_32 length;
+   if (swidth == NULL || (lengthw = png_strlen(swidth)) == 0 ||
+       swidth[0] == 45 /* '-' */ || !png_check_fp_string(swidth, lengthw))
+      png_error(png_ptr, "Invalid sCAL width");
 
-   png_debug1(1, "in %s storage function\n", "sCAL");
-   if (png_ptr == NULL || info_ptr == NULL)
-      return;
+   if (sheight == NULL || (lengthh = png_strlen(sheight)) == 0 ||
+       sheight[0] == 45 /* '-' */ || !png_check_fp_string(sheight, lengthh))
+      png_error(png_ptr, "Invalid sCAL height");
 
    info_ptr->scal_unit = (png_byte)unit;
 
-   length = png_strlen(swidth) + 1;
-   png_debug1(3, "allocating unit for info (%d bytes)\n", length);
-   info_ptr->scal_s_width = (png_charp)png_malloc_warn(png_ptr, length);
+   ++lengthw;
+
+   png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthw);
+
+   info_ptr->scal_s_width = (png_charp)png_malloc_warn(png_ptr, lengthw);
+
    if (info_ptr->scal_s_width == NULL)
    {
-      png_warning(png_ptr, "Memory allocation failed while processing sCAL.");
+      png_warning(png_ptr, "Memory allocation failed while processing sCAL");
+      return;
    }
-   png_memcpy(info_ptr->scal_s_width, swidth, (png_size_t)length);
 
-   length = png_strlen(sheight) + 1;
-   png_debug1(3, "allocating unit for info (%d bytes)\n", length);
-   info_ptr->scal_s_height = (png_charp)png_malloc_warn(png_ptr, length);
+   png_memcpy(info_ptr->scal_s_width, swidth, lengthw);
+
+   ++lengthh;
+
+   png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthh);
+
+   info_ptr->scal_s_height = (png_charp)png_malloc_warn(png_ptr, lengthh);
+
    if (info_ptr->scal_s_height == NULL)
    {
       png_free (png_ptr, info_ptr->scal_s_width);
-      png_warning(png_ptr, "Memory allocation failed while processing sCAL.");
+      info_ptr->scal_s_width = NULL;
+
+      png_warning(png_ptr, "Memory allocation failed while processing sCAL");
+      return;
    }
-   png_memcpy(info_ptr->scal_s_height, sheight, (png_size_t)length);
+
+   png_memcpy(info_ptr->scal_s_height, sheight, lengthh);
 
    info_ptr->valid |= PNG_INFO_sCAL;
-#ifdef PNG_FREE_ME_SUPPORTED
    info_ptr->free_me |= PNG_FREE_SCAL;
-#endif
 }
-#endif
-#endif
+
+#  ifdef PNG_FLOATING_POINT_SUPPORTED
+void PNGAPI
+png_set_sCAL(png_structp png_ptr, png_infop info_ptr, int unit, double width,
+    double height)
+{
+   png_debug1(1, "in %s storage function", "sCAL");
+
+   /* Check the arguments. */
+   if (width <= 0)
+      png_warning(png_ptr, "Invalid sCAL width ignored");
+
+   else if (height <= 0)
+      png_warning(png_ptr, "Invalid sCAL height ignored");
+
+   else
+   {
+      /* Convert 'width' and 'height' to ASCII. */
+      char swidth[PNG_sCAL_MAX_DIGITS+1];
+      char sheight[PNG_sCAL_MAX_DIGITS+1];
+
+      png_ascii_from_fp(png_ptr, swidth, sizeof swidth, width,
+         PNG_sCAL_PRECISION);
+      png_ascii_from_fp(png_ptr, sheight, sizeof sheight, height,
+         PNG_sCAL_PRECISION);
+
+      png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
+   }
+}
+#  endif
+
+#  ifdef PNG_FIXED_POINT_SUPPORTED
+void PNGAPI
+png_set_sCAL_fixed(png_structp png_ptr, png_infop info_ptr, int unit,
+    png_fixed_point width, png_fixed_point height)
+{
+   png_debug1(1, "in %s storage function", "sCAL");
+
+   /* Check the arguments. */
+   if (width <= 0)
+      png_warning(png_ptr, "Invalid sCAL width ignored");
+
+   else if (height <= 0)
+      png_warning(png_ptr, "Invalid sCAL height ignored");
+
+   else
+   {
+      /* Convert 'width' and 'height' to ASCII. */
+      char swidth[PNG_sCAL_MAX_DIGITS+1];
+      char sheight[PNG_sCAL_MAX_DIGITS+1];
+
+      png_ascii_from_fixed(png_ptr, swidth, sizeof swidth, width);
+      png_ascii_from_fixed(png_ptr, sheight, sizeof sheight, height);
+
+      png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight);
+   }
+}
+#  endif
 #endif
 
-#if defined(PNG_pHYs_SUPPORTED)
+#ifdef PNG_pHYs_SUPPORTED
 void PNGAPI
 png_set_pHYs(png_structp png_ptr, png_infop info_ptr,
-   png_uint_32 res_x, png_uint_32 res_y, int unit_type)
+    png_uint_32 res_x, png_uint_32 res_y, int unit_type)
 {
-   png_debug1(1, "in %s storage function\n", "pHYs");
+   png_debug1(1, "in %s storage function", "pHYs");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
@@ -510,164 +514,139 @@ png_set_pHYs(png_structp png_ptr, png_infop info_ptr,
 
 void PNGAPI
 png_set_PLTE(png_structp png_ptr, png_infop info_ptr,
-   png_colorp palette, int num_palette)
+    png_const_colorp palette, int num_palette)
 {
 
-   png_debug1(1, "in %s storage function\n", "PLTE");
+   png_debug1(1, "in %s storage function", "PLTE");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   /*
-    * It may not actually be necessary to set png_ptr->palette here;
+   if (num_palette < 0 || num_palette > PNG_MAX_PALETTE_LENGTH)
+   {
+      if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
+         png_error(png_ptr, "Invalid palette length");
+
+      else
+      {
+         png_warning(png_ptr, "Invalid palette length");
+         return;
+      }
+   }
+
+   /* It may not actually be necessary to set png_ptr->palette here;
     * we do it for backward compatibility with the way the png_handle_tRNS
     * function used to do the allocation.
     */
-#ifdef PNG_FREE_ME_SUPPORTED
    png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0);
-#endif
 
-   /* Changed in libpng-1.2.1 to allocate 256 instead of num_palette entries,
-      in case of an invalid PNG file that has too-large sample values. */
-   png_ptr->palette = (png_colorp)png_malloc(png_ptr,
-      256 * png_sizeof(png_color));
-   png_memset(png_ptr->palette, 0, 256 * png_sizeof(png_color));
-   png_memcpy(png_ptr->palette, palette, num_palette * png_sizeof (png_color));
+   /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead
+    * of num_palette entries, in case of an invalid PNG file that has
+    * too-large sample values.
+    */
+   png_ptr->palette = (png_colorp)png_calloc(png_ptr,
+       PNG_MAX_PALETTE_LENGTH * png_sizeof(png_color));
+
+   png_memcpy(png_ptr->palette, palette, num_palette * png_sizeof(png_color));
    info_ptr->palette = png_ptr->palette;
    info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette;
 
-#ifdef PNG_FREE_ME_SUPPORTED
    info_ptr->free_me |= PNG_FREE_PLTE;
-#else
-   png_ptr->flags |= PNG_FLAG_FREE_PLTE;
-#endif
 
    info_ptr->valid |= PNG_INFO_PLTE;
 }
 
-#if defined(PNG_sBIT_SUPPORTED)
+#ifdef PNG_sBIT_SUPPORTED
 void PNGAPI
 png_set_sBIT(png_structp png_ptr, png_infop info_ptr,
-   png_color_8p sig_bit)
+    png_const_color_8p sig_bit)
 {
-   png_debug1(1, "in %s storage function\n", "sBIT");
+   png_debug1(1, "in %s storage function", "sBIT");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   png_memcpy(&(info_ptr->sig_bit), sig_bit, png_sizeof (png_color_8));
+   png_memcpy(&(info_ptr->sig_bit), sig_bit, png_sizeof(png_color_8));
    info_ptr->valid |= PNG_INFO_sBIT;
 }
 #endif
 
-#if defined(PNG_sRGB_SUPPORTED)
+#ifdef PNG_sRGB_SUPPORTED
 void PNGAPI
-png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int intent)
+png_set_sRGB(png_structp png_ptr, png_infop info_ptr, int srgb_intent)
 {
-   png_debug1(1, "in %s storage function\n", "sRGB");
+   png_debug1(1, "in %s storage function", "sRGB");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   info_ptr->srgb_intent = (png_byte)intent;
+   info_ptr->srgb_intent = (png_byte)srgb_intent;
    info_ptr->valid |= PNG_INFO_sRGB;
 }
 
 void PNGAPI
 png_set_sRGB_gAMA_and_cHRM(png_structp png_ptr, png_infop info_ptr,
-   int intent)
+    int srgb_intent)
 {
-#if defined(PNG_gAMA_SUPPORTED)
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-   float file_gamma;
-#endif
-#ifdef PNG_FIXED_POINT_SUPPORTED
-   png_fixed_point int_file_gamma;
-#endif
-#endif
-#if defined(PNG_cHRM_SUPPORTED)
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-   float white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y;
-#endif
-#ifdef PNG_FIXED_POINT_SUPPORTED
-   png_fixed_point int_white_x, int_white_y, int_red_x, int_red_y, int_green_x,
-      int_green_y, int_blue_x, int_blue_y;
-#endif
-#endif
-   png_debug1(1, "in %s storage function\n", "sRGB_gAMA_and_cHRM");
+   png_debug1(1, "in %s storage function", "sRGB_gAMA_and_cHRM");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   png_set_sRGB(png_ptr, info_ptr, intent);
+   png_set_sRGB(png_ptr, info_ptr, srgb_intent);
 
-#if defined(PNG_gAMA_SUPPORTED)
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-   file_gamma = (float).45455;
-   png_set_gAMA(png_ptr, info_ptr, file_gamma);
-#endif
-#ifdef PNG_FIXED_POINT_SUPPORTED
-   int_file_gamma = 45455L;
-   png_set_gAMA_fixed(png_ptr, info_ptr, int_file_gamma);
-#endif
-#endif
-
-#if defined(PNG_cHRM_SUPPORTED)
-#ifdef PNG_FIXED_POINT_SUPPORTED
-   int_white_x = 31270L;
-   int_white_y = 32900L;
-   int_red_x   = 64000L;
-   int_red_y   = 33000L;
-   int_green_x = 30000L;
-   int_green_y = 60000L;
-   int_blue_x  = 15000L;
-   int_blue_y  =  6000L;
+#  ifdef PNG_gAMA_SUPPORTED
+   png_set_gAMA_fixed(png_ptr, info_ptr, PNG_GAMMA_sRGB_INVERSE);
+#  endif
 
+#  ifdef PNG_cHRM_SUPPORTED
    png_set_cHRM_fixed(png_ptr, info_ptr,
-      int_white_x, int_white_y, int_red_x, int_red_y, int_green_x, int_green_y,
-      int_blue_x, int_blue_y);
-#endif
-#ifdef PNG_FLOATING_POINT_SUPPORTED
-   white_x = (float).3127;
-   white_y = (float).3290;
-   red_x   = (float).64;
-   red_y   = (float).33;
-   green_x = (float).30;
-   green_y = (float).60;
-   blue_x  = (float).15;
-   blue_y  = (float).06;
-
-   png_set_cHRM(png_ptr, info_ptr,
-      white_x, white_y, red_x, red_y, green_x, green_y, blue_x, blue_y);
-#endif
-#endif
+      /* color      x       y */
+      /* white */ 31270, 32900,
+      /* red   */ 64000, 33000,
+      /* green */ 30000, 60000,
+      /* blue  */ 15000,  6000
+   );
+#  endif /* cHRM */
 }
-#endif
+#endif /* sRGB */
 
 
-#if defined(PNG_iCCP_SUPPORTED)
+#ifdef PNG_iCCP_SUPPORTED
 void PNGAPI
 png_set_iCCP(png_structp png_ptr, png_infop info_ptr,
-             png_charp name, int compression_type,
-             png_charp profile, png_uint_32 proflen)
+    png_const_charp name, int compression_type,
+    png_const_bytep profile, png_uint_32 proflen)
 {
    png_charp new_iccp_name;
-   png_charp new_iccp_profile;
+   png_bytep new_iccp_profile;
+   png_size_t length;
+
+   png_debug1(1, "in %s storage function", "iCCP");
 
-   png_debug1(1, "in %s storage function\n", "iCCP");
    if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL)
       return;
 
-   new_iccp_name = (png_charp)png_malloc_warn(png_ptr, png_strlen(name)+1);
+   length = png_strlen(name)+1;
+   new_iccp_name = (png_charp)png_malloc_warn(png_ptr, length);
+
    if (new_iccp_name == NULL)
    {
-      png_warning(png_ptr, "Insufficient memory to process iCCP chunk.");
+        png_warning(png_ptr, "Insufficient memory to process iCCP chunk");
       return;
    }
-   png_strcpy(new_iccp_name, name);
-   new_iccp_profile = (png_charp)png_malloc_warn(png_ptr, proflen);
+
+   png_memcpy(new_iccp_name, name, length);
+   new_iccp_profile = (png_bytep)png_malloc_warn(png_ptr, proflen);
+
    if (new_iccp_profile == NULL)
    {
       png_free (png_ptr, new_iccp_name);
-      png_warning(png_ptr, "Insufficient memory to process iCCP profile.");
+      png_warning(png_ptr,
+          "Insufficient memory to process iCCP profile");
       return;
    }
+
    png_memcpy(new_iccp_profile, profile, (png_size_t)proflen);
 
    png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0);
@@ -676,34 +655,34 @@ png_set_iCCP(png_structp png_ptr, png_infop info_ptr,
    info_ptr->iccp_name = new_iccp_name;
    info_ptr->iccp_profile = new_iccp_profile;
    /* Compression is always zero but is here so the API and info structure
-    * does not have to change if we introduce multiple compression types */
+    * does not have to change if we introduce multiple compression types
+    */
    info_ptr->iccp_compression = (png_byte)compression_type;
-#ifdef PNG_FREE_ME_SUPPORTED
    info_ptr->free_me |= PNG_FREE_ICCP;
-#endif
    info_ptr->valid |= PNG_INFO_iCCP;
 }
 #endif
 
-#if defined(PNG_TEXT_SUPPORTED)
+#ifdef PNG_TEXT_SUPPORTED
 void PNGAPI
-png_set_text(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
-   int num_text)
+png_set_text(png_structp png_ptr, png_infop info_ptr, png_const_textp text_ptr,
+    int num_text)
 {
    int ret;
-   ret=png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);
+   ret = png_set_text_2(png_ptr, info_ptr, text_ptr, num_text);
+
    if (ret)
-     png_error(png_ptr, "Insufficient memory to store text");
+      png_error(png_ptr, "Insufficient memory to store text");
 }
 
 int /* PRIVATE */
-png_set_text_2(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
-   int num_text)
+png_set_text_2(png_structp png_ptr, png_infop info_ptr,
+    png_const_textp text_ptr, int num_text)
 {
    int i;
 
-   png_debug1(1, "in %s storage function\n", (png_ptr->chunk_name[0] == '\0' ?
-      "text" : (png_const_charp)png_ptr->chunk_name));
+   png_debug1(1, "in %lx storage function", png_ptr == NULL ? "unexpected" :
+      (unsigned long)png_ptr->chunk_name);
 
    if (png_ptr == NULL || info_ptr == NULL || num_text == 0)
       return(0);
@@ -722,77 +701,93 @@ png_set_text_2(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
          info_ptr->max_text = info_ptr->num_text + num_text + 8;
          old_text = info_ptr->text;
          info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
-            (png_uint_32)(info_ptr->max_text * png_sizeof (png_text)));
+            (png_size_t)(info_ptr->max_text * png_sizeof(png_text)));
+
          if (info_ptr->text == NULL)
-           {
-             png_free(png_ptr, old_text);
-             return(1);
-           }
+         {
+            png_free(png_ptr, old_text);
+            return(1);
+         }
+
          png_memcpy(info_ptr->text, old_text, (png_size_t)(old_max *
-            png_sizeof(png_text)));
+             png_sizeof(png_text)));
          png_free(png_ptr, old_text);
       }
+
       else
       {
          info_ptr->max_text = num_text + 8;
          info_ptr->num_text = 0;
          info_ptr->text = (png_textp)png_malloc_warn(png_ptr,
-            (png_uint_32)(info_ptr->max_text * png_sizeof (png_text)));
+             (png_size_t)(info_ptr->max_text * png_sizeof(png_text)));
          if (info_ptr->text == NULL)
-           return(1);
-#ifdef PNG_FREE_ME_SUPPORTED
+            return(1);
          info_ptr->free_me |= PNG_FREE_TEXT;
-#endif
       }
-      png_debug1(3, "allocated %d entries for info_ptr->text\n",
-         info_ptr->max_text);
+
+      png_debug1(3, "allocated %d entries for info_ptr->text",
+          info_ptr->max_text);
    }
    for (i = 0; i < num_text; i++)
    {
-      png_size_t text_length,key_len;
-      png_size_t lang_len,lang_key_len;
+      png_size_t text_length, key_len;
+      png_size_t lang_len, lang_key_len;
       png_textp textp = &(info_ptr->text[info_ptr->num_text]);
 
       if (text_ptr[i].key == NULL)
           continue;
 
+      if (text_ptr[i].compression < PNG_TEXT_COMPRESSION_NONE ||
+          text_ptr[i].compression >= PNG_TEXT_COMPRESSION_LAST)
+      {
+         png_warning(png_ptr, "text compression mode is out of range");
+         continue;
+      }
+
       key_len = png_strlen(text_ptr[i].key);
 
-      if(text_ptr[i].compression <= 0)
+      if (text_ptr[i].compression <= 0)
       {
-        lang_len = 0;
-        lang_key_len = 0;
+         lang_len = 0;
+         lang_key_len = 0;
       }
+
       else
-#ifdef PNG_iTXt_SUPPORTED
+#  ifdef PNG_iTXt_SUPPORTED
       {
-        /* set iTXt data */
-        if (text_ptr[i].lang != NULL)
-          lang_len = png_strlen(text_ptr[i].lang);
-        else
-          lang_len = 0;
-        if (text_ptr[i].lang_key != NULL)
-          lang_key_len = png_strlen(text_ptr[i].lang_key);
-        else
-          lang_key_len = 0;
+         /* Set iTXt data */
+
+         if (text_ptr[i].lang != NULL)
+            lang_len = png_strlen(text_ptr[i].lang);
+
+         else
+            lang_len = 0;
+
+         if (text_ptr[i].lang_key != NULL)
+            lang_key_len = png_strlen(text_ptr[i].lang_key);
+
+         else
+            lang_key_len = 0;
       }
-#else
+#  else /* PNG_iTXt_SUPPORTED */
       {
-        png_warning(png_ptr, "iTXt chunk not supported.");
-        continue;
+         png_warning(png_ptr, "iTXt chunk not supported");
+         continue;
       }
-#endif
+#  endif
 
       if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0')
       {
          text_length = 0;
-#ifdef PNG_iTXt_SUPPORTED
-         if(text_ptr[i].compression > 0)
+#  ifdef PNG_iTXt_SUPPORTED
+         if (text_ptr[i].compression > 0)
             textp->compression = PNG_ITXT_COMPRESSION_NONE;
+
          else
-#endif
+#  endif
             textp->compression = PNG_TEXT_COMPRESSION_NONE;
       }
+
       else
       {
          text_length = png_strlen(text_ptr[i].text);
@@ -800,420 +795,490 @@ png_set_text_2(png_structp png_ptr, png_infop info_ptr, png_textp text_ptr,
       }
 
       textp->key = (png_charp)png_malloc_warn(png_ptr,
-         (png_uint_32)(key_len + text_length + lang_len + lang_key_len + 4));
+          (png_size_t)
+          (key_len + text_length + lang_len + lang_key_len + 4));
+
       if (textp->key == NULL)
-        return(1);
-      png_debug2(2, "Allocated %lu bytes at %x in png_set_text\n",
-         (png_uint_32)(key_len + lang_len + lang_key_len + text_length + 4),
-         (int)textp->key);
-
-      png_memcpy(textp->key, text_ptr[i].key,
-         (png_size_t)(key_len));
-      *(textp->key+key_len) = '\0';
-#ifdef PNG_iTXt_SUPPORTED
+         return(1);
+
+      png_debug2(2, "Allocated %lu bytes at %p in png_set_text",
+          (unsigned long)(png_uint_32)
+          (key_len + lang_len + lang_key_len + text_length + 4),
+          textp->key);
+
+      png_memcpy(textp->key, text_ptr[i].key,(png_size_t)(key_len));
+      *(textp->key + key_len) = '\0';
+
       if (text_ptr[i].compression > 0)
       {
-         textp->lang=textp->key + key_len + 1;
+         textp->lang = textp->key + key_len + 1;
          png_memcpy(textp->lang, text_ptr[i].lang, lang_len);
-         *(textp->lang+lang_len) = '\0';
-         textp->lang_key=textp->lang + lang_len + 1;
+         *(textp->lang + lang_len) = '\0';
+         textp->lang_key = textp->lang + lang_len + 1;
          png_memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len);
-         *(textp->lang_key+lang_key_len) = '\0';
-         textp->text=textp->lang_key + lang_key_len + 1;
+         *(textp->lang_key + lang_key_len) = '\0';
+         textp->text = textp->lang_key + lang_key_len + 1;
       }
+
       else
-#endif
       {
-#ifdef PNG_iTXt_SUPPORTED
          textp->lang=NULL;
          textp->lang_key=NULL;
-#endif
-         textp->text=textp->key + key_len + 1;
+         textp->text = textp->key + key_len + 1;
       }
-      if(text_length)
+
+      if (text_length)
          png_memcpy(textp->text, text_ptr[i].text,
-            (png_size_t)(text_length));
-      *(textp->text+text_length) = '\0';
+             (png_size_t)(text_length));
+
+      *(textp->text + text_length) = '\0';
 
-#ifdef PNG_iTXt_SUPPORTED
-      if(textp->compression > 0)
+#  ifdef PNG_iTXt_SUPPORTED
+      if (textp->compression > 0)
       {
          textp->text_length = 0;
          textp->itxt_length = text_length;
       }
+
       else
-#endif
+#  endif
       {
          textp->text_length = text_length;
-#ifdef PNG_iTXt_SUPPORTED
          textp->itxt_length = 0;
-#endif
       }
-      info_ptr->text[info_ptr->num_text]= *textp;
+
       info_ptr->num_text++;
-      png_debug1(3, "transferred text chunk %d\n", info_ptr->num_text);
+      png_debug1(3, "transferred text chunk %d", info_ptr->num_text);
    }
    return(0);
 }
 #endif
 
-#if defined(PNG_tIME_SUPPORTED)
+#ifdef PNG_tIME_SUPPORTED
 void PNGAPI
-png_set_tIME(png_structp png_ptr, png_infop info_ptr, png_timep mod_time)
+png_set_tIME(png_structp png_ptr, png_infop info_ptr, png_const_timep mod_time)
 {
-   png_debug1(1, "in %s storage function\n", "tIME");
+   png_debug1(1, "in %s storage function", "tIME");
+
    if (png_ptr == NULL || info_ptr == NULL ||
        (png_ptr->mode & PNG_WROTE_tIME))
       return;
 
-   png_memcpy(&(info_ptr->mod_time), mod_time, png_sizeof (png_time));
+   if (mod_time->month == 0   || mod_time->month > 12  ||
+       mod_time->day   == 0   || mod_time->day   > 31  ||
+       mod_time->hour  > 23   || mod_time->minute > 59 ||
+       mod_time->second > 60)
+   {
+      png_warning(png_ptr, "Ignoring invalid time value");
+      return;
+   }
+
+   png_memcpy(&(info_ptr->mod_time), mod_time, png_sizeof(png_time));
    info_ptr->valid |= PNG_INFO_tIME;
 }
 #endif
 
-#if defined(PNG_tRNS_SUPPORTED)
+#ifdef PNG_tRNS_SUPPORTED
 void PNGAPI
 png_set_tRNS(png_structp png_ptr, png_infop info_ptr,
-   png_bytep trans, int num_trans, png_color_16p trans_values)
+    png_const_bytep trans_alpha, int num_trans, png_const_color_16p trans_color)
 {
-   png_debug1(1, "in %s storage function\n", "tRNS");
+   png_debug1(1, "in %s storage function", "tRNS");
+
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   if (trans != NULL)
+   if (trans_alpha != NULL)
    {
-       /*
-        * It may not actually be necessary to set png_ptr->trans here;
+       /* It may not actually be necessary to set png_ptr->trans_alpha here;
         * we do it for backward compatibility with the way the png_handle_tRNS
         * function used to do the allocation.
         */
-#ifdef PNG_FREE_ME_SUPPORTED
+
        png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0);
-#endif
-       /* Changed from num_trans to 256 in version 1.2.1 */
-       png_ptr->trans = info_ptr->trans = (png_bytep)png_malloc(png_ptr,
-           (png_uint_32)256);
-       png_memcpy(info_ptr->trans, trans, (png_size_t)num_trans);
-#ifdef PNG_FREE_ME_SUPPORTED
-       info_ptr->free_me |= PNG_FREE_TRNS;
-#else
-       png_ptr->flags |= PNG_FLAG_FREE_TRNS;
-#endif
+
+       /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */
+       png_ptr->trans_alpha = info_ptr->trans_alpha =
+           (png_bytep)png_malloc(png_ptr, (png_size_t)PNG_MAX_PALETTE_LENGTH);
+
+       if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH)
+          png_memcpy(info_ptr->trans_alpha, trans_alpha, (png_size_t)num_trans);
    }
 
-   if (trans_values != NULL)
+   if (trans_color != NULL)
    {
-      png_memcpy(&(info_ptr->trans_values), trans_values,
+      int sample_max = (1 << info_ptr->bit_depth);
+
+      if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY &&
+          (int)trans_color->gray > sample_max) ||
+          (info_ptr->color_type == PNG_COLOR_TYPE_RGB &&
+          ((int)trans_color->red > sample_max ||
+          (int)trans_color->green > sample_max ||
+          (int)trans_color->blue > sample_max)))
+         png_warning(png_ptr,
+            "tRNS chunk has out-of-range samples for bit_depth");
+
+      png_memcpy(&(info_ptr->trans_color), trans_color,
          png_sizeof(png_color_16));
+
       if (num_trans == 0)
-        num_trans = 1;
+         num_trans = 1;
    }
+
    info_ptr->num_trans = (png_uint_16)num_trans;
-   info_ptr->valid |= PNG_INFO_tRNS;
+
+   if (num_trans != 0)
+   {
+      info_ptr->valid |= PNG_INFO_tRNS;
+      info_ptr->free_me |= PNG_FREE_TRNS;
+   }
 }
 #endif
 
-#if defined(PNG_sPLT_SUPPORTED)
+#ifdef PNG_sPLT_SUPPORTED
 void PNGAPI
 png_set_sPLT(png_structp png_ptr,
-             png_infop info_ptr, png_sPLT_tp entries, int nentries)
+    png_infop info_ptr, png_const_sPLT_tp entries, int nentries)
+/*
+ *  entries        - array of png_sPLT_t structures
+ *                   to be added to the list of palettes
+ *                   in the info structure.
+ *
+ *  nentries       - number of palette structures to be
+ *                   added.
+ */
 {
-    png_sPLT_tp np;
-    int i;
+   png_sPLT_tp np;
+   int i;
 
-    np = (png_sPLT_tp)png_malloc_warn(png_ptr,
-        (info_ptr->splt_palettes_num + nentries) * png_sizeof(png_sPLT_t));
-    if (np == NULL)
-    {
-      png_warning(png_ptr, "No memory for sPLT palettes.");
+   if (png_ptr == NULL || info_ptr == NULL)
       return;
-    }
 
-    png_memcpy(np, info_ptr->splt_palettes,
-           info_ptr->splt_palettes_num * png_sizeof(png_sPLT_t));
-    png_free(png_ptr, info_ptr->splt_palettes);
-    info_ptr->splt_palettes=NULL;
+   np = (png_sPLT_tp)png_malloc_warn(png_ptr,
+       (info_ptr->splt_palettes_num + nentries) *
+       (png_size_t)png_sizeof(png_sPLT_t));
 
-    for (i = 0; i < nentries; i++)
-    {
-        png_sPLT_tp to = np + info_ptr->splt_palettes_num + i;
-        png_sPLT_tp from = entries + i;
-
-        to->name = (png_charp)png_malloc(png_ptr,
-            png_strlen(from->name) + 1);
-        /* TODO: use png_malloc_warn */
-        png_strcpy(to->name, from->name);
-        to->entries = (png_sPLT_entryp)png_malloc(png_ptr,
-            from->nentries * png_sizeof(png_sPLT_t));
-        /* TODO: use png_malloc_warn */
-        png_memcpy(to->entries, from->entries,
-            from->nentries * png_sizeof(png_sPLT_t));
-        to->nentries = from->nentries;
-        to->depth = from->depth;
-    }
+   if (np == NULL)
+   {
+      png_warning(png_ptr, "No memory for sPLT palettes");
+      return;
+   }
 
-    info_ptr->splt_palettes = np;
-    info_ptr->splt_palettes_num += nentries;
-    info_ptr->valid |= PNG_INFO_sPLT;
-#ifdef PNG_FREE_ME_SUPPORTED
-    info_ptr->free_me |= PNG_FREE_SPLT;
-#endif
+   png_memcpy(np, info_ptr->splt_palettes,
+       info_ptr->splt_palettes_num * png_sizeof(png_sPLT_t));
+
+   png_free(png_ptr, info_ptr->splt_palettes);
+   info_ptr->splt_palettes=NULL;
+
+   for (i = 0; i < nentries; i++)
+   {
+      png_sPLT_tp to = np + info_ptr->splt_palettes_num + i;
+      png_const_sPLT_tp from = entries + i;
+      png_size_t length;
+
+      length = png_strlen(from->name) + 1;
+      to->name = (png_charp)png_malloc_warn(png_ptr, length);
+
+      if (to->name == NULL)
+      {
+         png_warning(png_ptr,
+             "Out of memory while processing sPLT chunk");
+         continue;
+      }
+
+      png_memcpy(to->name, from->name, length);
+      to->entries = (png_sPLT_entryp)png_malloc_warn(png_ptr,
+          from->nentries * png_sizeof(png_sPLT_entry));
+
+      if (to->entries == NULL)
+      {
+         png_warning(png_ptr,
+             "Out of memory while processing sPLT chunk");
+         png_free(png_ptr, to->name);
+         to->name = NULL;
+         continue;
+      }
+
+      png_memcpy(to->entries, from->entries,
+          from->nentries * png_sizeof(png_sPLT_entry));
+
+      to->nentries = from->nentries;
+      to->depth = from->depth;
+   }
+
+   info_ptr->splt_palettes = np;
+   info_ptr->splt_palettes_num += nentries;
+   info_ptr->valid |= PNG_INFO_sPLT;
+   info_ptr->free_me |= PNG_FREE_SPLT;
 }
 #endif /* PNG_sPLT_SUPPORTED */
 
-#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+#ifdef PNG_UNKNOWN_CHUNKS_SUPPORTED
 void PNGAPI
 png_set_unknown_chunks(png_structp png_ptr,
-   png_infop info_ptr, png_unknown_chunkp unknowns, int num_unknowns)
+   png_infop info_ptr, png_const_unknown_chunkp unknowns, int num_unknowns)
 {
-    png_unknown_chunkp np;
-    int i;
+   png_unknown_chunkp np;
+   int i;
 
-    if (png_ptr == NULL || info_ptr == NULL || num_unknowns == 0)
-        return;
+   if (png_ptr == NULL || info_ptr == NULL || num_unknowns == 0)
+      return;
 
-    np = (png_unknown_chunkp)png_malloc_warn(png_ptr,
-        (info_ptr->unknown_chunks_num + num_unknowns) *
-        png_sizeof(png_unknown_chunk));
-    if (np == NULL)
-    {
-       png_warning(png_ptr, "Out of memory while processing unknown chunk.");
-       return;
-    }
+   np = (png_unknown_chunkp)png_malloc_warn(png_ptr,
+       (png_size_t)(info_ptr->unknown_chunks_num + num_unknowns) *
+       png_sizeof(png_unknown_chunk));
 
-    png_memcpy(np, info_ptr->unknown_chunks,
-           info_ptr->unknown_chunks_num * png_sizeof(png_unknown_chunk));
-    png_free(png_ptr, info_ptr->unknown_chunks);
-    info_ptr->unknown_chunks=NULL;
+   if (np == NULL)
+   {
+      png_warning(png_ptr,
+          "Out of memory while processing unknown chunk");
+      return;
+   }
 
-    for (i = 0; i < num_unknowns; i++)
-    {
-        png_unknown_chunkp to = np + info_ptr->unknown_chunks_num + i;
-        png_unknown_chunkp from = unknowns + i;
-
-        png_strncpy((png_charp)to->name, (png_charp)from->name, 5);
-        to->data = (png_bytep)png_malloc_warn(png_ptr, from->size);
-        if (to->data == NULL)
-        {
-           png_warning(png_ptr, "Out of memory processing unknown chunk.");
-        }
-        else
-        {
-           png_memcpy(to->data, from->data, from->size);
-           to->size = from->size;
-
-           /* note our location in the read or write sequence */
-           to->location = (png_byte)(png_ptr->mode & 0xff);
-        }
-    }
+   png_memcpy(np, info_ptr->unknown_chunks,
+       (png_size_t)info_ptr->unknown_chunks_num *
+       png_sizeof(png_unknown_chunk));
 
-    info_ptr->unknown_chunks = np;
-    info_ptr->unknown_chunks_num += num_unknowns;
-#ifdef PNG_FREE_ME_SUPPORTED
-    info_ptr->free_me |= PNG_FREE_UNKN;
-#endif
+   png_free(png_ptr, info_ptr->unknown_chunks);
+   info_ptr->unknown_chunks = NULL;
+
+   for (i = 0; i < num_unknowns; i++)
+   {
+      png_unknown_chunkp to = np + info_ptr->unknown_chunks_num + i;
+      png_const_unknown_chunkp from = unknowns + i;
+
+      png_memcpy(to->name, from->name, png_sizeof(from->name));
+      to->name[png_sizeof(to->name)-1] = '\0';
+      to->size = from->size;
+
+      /* Note our location in the read or write sequence */
+      to->location = (png_byte)(png_ptr->mode & 0xff);
+
+      if (from->size == 0)
+         to->data=NULL;
+
+      else
+      {
+         to->data = (png_bytep)png_malloc_warn(png_ptr,
+             (png_size_t)from->size);
+
+         if (to->data == NULL)
+         {
+            png_warning(png_ptr,
+                "Out of memory while processing unknown chunk");
+            to->size = 0;
+         }
+
+         else
+            png_memcpy(to->data, from->data, from->size);
+      }
+   }
+
+   info_ptr->unknown_chunks = np;
+   info_ptr->unknown_chunks_num += num_unknowns;
+   info_ptr->free_me |= PNG_FREE_UNKN;
 }
+
 void PNGAPI
 png_set_unknown_chunk_location(png_structp png_ptr, png_infop info_ptr,
-   int chunk, int location)
+    int chunk, int location)
 {
-   if(png_ptr != NULL && info_ptr != NULL && chunk >= 0 && chunk <
-         (int)info_ptr->unknown_chunks_num)
+   if (png_ptr != NULL && info_ptr != NULL && chunk >= 0 && chunk <
+       info_ptr->unknown_chunks_num)
       info_ptr->unknown_chunks[chunk].location = (png_byte)location;
 }
 #endif
 
-#if defined(PNG_READ_EMPTY_PLTE_SUPPORTED) || \
-    defined(PNG_WRITE_EMPTY_PLTE_SUPPORTED)
-void PNGAPI
-png_permit_empty_plte (png_structp png_ptr, int empty_plte_permitted)
-{
-   /* This function is deprecated in favor of png_permit_mng_features()
-      and will be removed from libpng-2.0.0 */
-   png_debug(1, "in png_permit_empty_plte, DEPRECATED.\n");
-   if (png_ptr == NULL)
-      return;
-   png_ptr->mng_features_permitted = (png_byte)
-     ((png_ptr->mng_features_permitted & (~(PNG_FLAG_MNG_EMPTY_PLTE))) |
-     ((empty_plte_permitted & PNG_FLAG_MNG_EMPTY_PLTE)));
-}
-#endif
 
-#if defined(PNG_MNG_FEATURES_SUPPORTED)
+#ifdef PNG_MNG_FEATURES_SUPPORTED
 png_uint_32 PNGAPI
 png_permit_mng_features (png_structp png_ptr, png_uint_32 mng_features)
 {
-   png_debug(1, "in png_permit_mng_features\n");
+   png_debug(1, "in png_permit_mng_features");
+
    if (png_ptr == NULL)
       return (png_uint_32)0;
+
    png_ptr->mng_features_permitted =
-     (png_byte)(mng_features & PNG_ALL_MNG_FEATURES);
+       (png_byte)(mng_features & PNG_ALL_MNG_FEATURES);
+
    return (png_uint_32)png_ptr->mng_features_permitted;
 }
 #endif
 
-#if defined(PNG_UNKNOWN_CHUNKS_SUPPORTED)
+#ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED
 void PNGAPI
-png_set_keep_unknown_chunks(png_structp png_ptr, int keep, png_bytep
-   chunk_list, int num_chunks)
+png_set_keep_unknown_chunks(png_structp png_ptr, int keep, png_const_bytep
+    chunk_list, int num_chunks)
 {
-    png_bytep new_list, p;
-    int i, old_num_chunks;
-    if (num_chunks == 0)
-    {
-      if(keep == PNG_HANDLE_CHUNK_ALWAYS || keep == PNG_HANDLE_CHUNK_IF_SAFE)
-        png_ptr->flags |= PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
+   png_bytep new_list, p;
+   int i, old_num_chunks;
+   if (png_ptr == NULL)
+      return;
+
+   if (num_chunks == 0)
+   {
+      if (keep == PNG_HANDLE_CHUNK_ALWAYS || keep == PNG_HANDLE_CHUNK_IF_SAFE)
+         png_ptr->flags |= PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
+
       else
-        png_ptr->flags &= ~PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
+         png_ptr->flags &= ~PNG_FLAG_KEEP_UNKNOWN_CHUNKS;
+
+      if (keep == PNG_HANDLE_CHUNK_ALWAYS)
+         png_ptr->flags |= PNG_FLAG_KEEP_UNSAFE_CHUNKS;
 
-      if(keep == PNG_HANDLE_CHUNK_ALWAYS)
-        png_ptr->flags |= PNG_FLAG_KEEP_UNSAFE_CHUNKS;
       else
-        png_ptr->flags &= ~PNG_FLAG_KEEP_UNSAFE_CHUNKS;
+         png_ptr->flags &= ~PNG_FLAG_KEEP_UNSAFE_CHUNKS;
+
       return;
-    }
-    if (chunk_list == NULL)
+   }
+
+   if (chunk_list == NULL)
       return;
-    old_num_chunks=png_ptr->num_chunk_list;
-    new_list=(png_bytep)png_malloc(png_ptr,
-       (png_uint_32)(5*(num_chunks+old_num_chunks)));
-    if(png_ptr->chunk_list != NULL)
-    {
-       png_memcpy(new_list, png_ptr->chunk_list,
+
+   old_num_chunks = png_ptr->num_chunk_list;
+   new_list=(png_bytep)png_malloc(png_ptr,
+       (png_size_t)(5*(num_chunks + old_num_chunks)));
+
+   if (png_ptr->chunk_list != NULL)
+   {
+      png_memcpy(new_list, png_ptr->chunk_list,
           (png_size_t)(5*old_num_chunks));
-       png_free(png_ptr, png_ptr->chunk_list);
-       png_ptr->chunk_list=NULL;
-    }
-    png_memcpy(new_list+5*old_num_chunks, chunk_list,
+      png_free(png_ptr, png_ptr->chunk_list);
+      png_ptr->chunk_list=NULL;
+   }
+
+   png_memcpy(new_list + 5*old_num_chunks, chunk_list,
        (png_size_t)(5*num_chunks));
-    for (p=new_list+5*old_num_chunks+4, i=0; i<num_chunks; i++, p+=5)
-       *p=(png_byte)keep;
-    png_ptr->num_chunk_list=old_num_chunks+num_chunks;
-    png_ptr->chunk_list=new_list;
-#ifdef PNG_FREE_ME_SUPPORTED
-    png_ptr->free_me |= PNG_FREE_LIST;
-#endif
+
+   for (p = new_list + 5*old_num_chunks + 4, i = 0; i<num_chunks; i++, p += 5)
+      *p=(png_byte)keep;
+
+   png_ptr->num_chunk_list = old_num_chunks + num_chunks;
+   png_ptr->chunk_list = new_list;
+   png_ptr->free_me |= PNG_FREE_LIST;
 }
 #endif
 
-#if defined(PNG_READ_USER_CHUNKS_SUPPORTED)
+#ifdef PNG_READ_USER_CHUNKS_SUPPORTED
 void PNGAPI
 png_set_read_user_chunk_fn(png_structp png_ptr, png_voidp user_chunk_ptr,
-   png_user_chunk_ptr read_user_chunk_fn)
+    png_user_chunk_ptr read_user_chunk_fn)
 {
-   png_debug(1, "in png_set_read_user_chunk_fn\n");
+   png_debug(1, "in png_set_read_user_chunk_fn");
+
+   if (png_ptr == NULL)
+      return;
+
    png_ptr->read_user_chunk_fn = read_user_chunk_fn;
    png_ptr->user_chunk_ptr = user_chunk_ptr;
 }
 #endif
 
-#if defined(PNG_INFO_IMAGE_SUPPORTED)
+#ifdef PNG_INFO_IMAGE_SUPPORTED
 void PNGAPI
 png_set_rows(png_structp png_ptr, png_infop info_ptr, png_bytepp row_pointers)
 {
-   png_debug1(1, "in %s storage function\n", "rows");
+   png_debug1(1, "in %s storage function", "rows");
 
    if (png_ptr == NULL || info_ptr == NULL)
       return;
 
-   if(info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
+   if (info_ptr->row_pointers && (info_ptr->row_pointers != row_pointers))
       png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0);
+
    info_ptr->row_pointers = row_pointers;
-   if(row_pointers)
+
+   if (row_pointers)
       info_ptr->valid |= PNG_INFO_IDAT;
 }
 #endif
 
-#ifdef PNG_WRITE_SUPPORTED
 void PNGAPI
-png_set_compression_buffer_size(png_structp png_ptr, png_uint_32 size)
+png_set_compression_buffer_size(png_structp png_ptr, png_size_t size)
 {
-    if(png_ptr->zbuf)
-       png_free(png_ptr, png_ptr->zbuf);
-    png_ptr->zbuf_size = (png_size_t)size;
+    if (png_ptr == NULL)
+       return;
+
+    png_free(png_ptr, png_ptr->zbuf);
+
+    if (size > ZLIB_IO_MAX)
+    {
+       png_warning(png_ptr, "Attempt to set buffer size beyond max ignored");
+       png_ptr->zbuf_size = ZLIB_IO_MAX;
+       size = ZLIB_IO_MAX; /* must fit */
+    }
+
+    else
+       png_ptr->zbuf_size = (uInt)size;
+
     png_ptr->zbuf = (png_bytep)png_malloc(png_ptr, size);
+
+    /* The following ensures a relatively safe failure if this gets called while
+     * the buffer is actually in use.
+     */
     png_ptr->zstream.next_out = png_ptr->zbuf;
-    png_ptr->zstream.avail_out = (uInt)png_ptr->zbuf_size;
+    png_ptr->zstream.avail_out = 0;
+    png_ptr->zstream.avail_in = 0;
 }
-#endif
 
 void PNGAPI
 png_set_invalid(png_structp png_ptr, png_infop info_ptr, int mask)
 {
    if (png_ptr && info_ptr)
-      info_ptr->valid &= ~(mask);
+      info_ptr->valid &= ~mask;
 }
 
 
-#ifndef PNG_1_0_X
-#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
-/* this function was added to libpng 1.2.0 and should always exist by default */
+
+#ifdef PNG_SET_USER_LIMITS_SUPPORTED
+/* This function was added to libpng 1.2.6 */
 void PNGAPI
-png_set_asm_flags (png_structp png_ptr, png_uint_32 asm_flags)
+png_set_user_limits (png_structp png_ptr, png_uint_32 user_width_max,
+    png_uint_32 user_height_max)
 {
-    png_uint_32 settable_asm_flags;
-    png_uint_32 settable_mmx_flags;
-
-    settable_mmx_flags =
-#ifdef PNG_HAVE_ASSEMBLER_COMBINE_ROW
-                         PNG_ASM_FLAG_MMX_READ_COMBINE_ROW  |
-#endif
-#ifdef PNG_HAVE_ASSEMBLER_READ_INTERLACE
-                         PNG_ASM_FLAG_MMX_READ_INTERLACE    |
-#endif
-#ifdef PNG_HAVE_ASSEMBLER_READ_FILTER_ROW
-                         PNG_ASM_FLAG_MMX_READ_FILTER_SUB   |
-                         PNG_ASM_FLAG_MMX_READ_FILTER_UP    |
-                         PNG_ASM_FLAG_MMX_READ_FILTER_AVG   |
-                         PNG_ASM_FLAG_MMX_READ_FILTER_PAETH |
-#endif
-                         0;
-
-    /* could be some non-MMX ones in the future, but not currently: */
-    settable_asm_flags = settable_mmx_flags;
-
-    if (!(png_ptr->asm_flags & PNG_ASM_FLAG_MMX_SUPPORT_COMPILED) ||
-        !(png_ptr->asm_flags & PNG_ASM_FLAG_MMX_SUPPORT_IN_CPU))
-    {
-        /* clear all MMX flags if MMX isn't supported */
-        settable_asm_flags &= ~settable_mmx_flags;
-        png_ptr->asm_flags &= ~settable_mmx_flags;
-    }
-
-    /* we're replacing the settable bits with those passed in by the user,
-     * so first zero them out of the master copy, then logical-OR in the
-     * allowed subset that was requested */
+   /* Images with dimensions larger than these limits will be
+    * rejected by png_set_IHDR().  To accept any PNG datastream
+    * regardless of dimensions, set both limits to 0x7ffffffL.
+    */
+   if (png_ptr == NULL)
+      return;
 
-    png_ptr->asm_flags &= ~settable_asm_flags;               /* zero them */
-    png_ptr->asm_flags |= (asm_flags & settable_asm_flags);  /* set them */
+   png_ptr->user_width_max = user_width_max;
+   png_ptr->user_height_max = user_height_max;
 }
-#endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
 
-#ifdef PNG_ASSEMBLER_CODE_SUPPORTED
-/* this function was added to libpng 1.2.0 */
+/* This function was added to libpng 1.4.0 */
 void PNGAPI
-png_set_mmx_thresholds (png_structp png_ptr,
-                        png_byte mmx_bitdepth_threshold,
-                        png_uint_32 mmx_rowbytes_threshold)
+png_set_chunk_cache_max (png_structp png_ptr,
+   png_uint_32 user_chunk_cache_max)
 {
-    png_ptr->mmx_bitdepth_threshold = mmx_bitdepth_threshold;
-    png_ptr->mmx_rowbytes_threshold = mmx_rowbytes_threshold;
+    if (png_ptr)
+       png_ptr->user_chunk_cache_max = user_chunk_cache_max;
 }
-#endif /* ?PNG_ASSEMBLER_CODE_SUPPORTED */
 
-#ifdef PNG_SET_USER_LIMITS_SUPPORTED
-/* this function was added to libpng 1.2.6 */
+/* This function was added to libpng 1.4.1 */
 void PNGAPI
-png_set_user_limits (png_structp png_ptr, png_uint_32 user_width_max,
-    png_uint_32 user_height_max)
+png_set_chunk_malloc_max (png_structp png_ptr,
+    png_alloc_size_t user_chunk_malloc_max)
 {
-    /* Images with dimensions larger than these limits will be
-     * rejected by png_set_IHDR().  To accept any PNG datastream
-     * regardless of dimensions, set both limits to 0x7ffffffL.
-     */
-    png_ptr->user_width_max = user_width_max;
-    png_ptr->user_height_max = user_height_max;
+   if (png_ptr)
+      png_ptr->user_chunk_malloc_max = user_chunk_malloc_max;
 }
 #endif /* ?PNG_SET_USER_LIMITS_SUPPORTED */
 
-#endif /* ?PNG_1_0_X */
+
+#ifdef PNG_BENIGN_ERRORS_SUPPORTED
+void PNGAPI
+png_set_benign_errors(png_structp png_ptr, int allowed)
+{
+   png_debug(1, "in png_set_benign_errors");
+
+   if (allowed)
+      png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN;
+
+   else
+      png_ptr->flags &= ~PNG_FLAG_BENIGN_ERRORS_WARN;
+}
+#endif /* PNG_BENIGN_ERRORS_SUPPORTED */
+#endif /* PNG_READ_SUPPORTED || PNG_WRITE_SUPPORTED */